NotebookLM master-file repair pattern

Use this reference for large master files built from NotebookLM sources.

Durable lessons

1. Batch by source index, usually 3 to 5 sources per batch.
2. Verify both English and Vietnamese summaries before writing each batch.
3. Detect corrupted Vietnamese text by scanning for mojibake markers such as Ã, Ä, VÄ, and BÃ.
4. Detect stale NotebookLM auth output by scanning for Authentication Error, Authentication expired, and empty summary fields.
5. Use source IDs from the Markdown line format - **ID:** \...`. Do not assume plainID:` formatting.
6. Prefer stream: false for local router translation calls when complete JSON responses are more stable than stream parsing.
7. If translation times out, reduce batch size and retry only the unconfirmed candidates.
8. Write only after the whole batch passes validation.

Recommended validation checks

For each source block, confirm:

1. one title line beginning with ###
2. one ID line
3. one keyword line
4. one English summary line
5. one Vietnamese summary line
6. no authentication placeholder
7. no mojibake markers
8. no empty summary field

Workflow note

If the user asks to review only at the end, continue across batches and keep the final parent task blocked for one review. Do not block after every batch unless the user explicitly requests batch-by-batch approval.